Historically, measles vaccination campaigns using a live, attenuated vaccine have been very effective and are attributed to an 85% reduction in measles mortality since the 1980's. While the syringes used in these campaigns have been demonstrated to be safe and effective, their use poses logistical issues centered on proper disposal. Aerosol delivery has been intensively investigated and recently has been quite successful. Currently, the World Health Organization (WHO) recommends that optimal vaccination to control measles outbreaks should occur in children at nine months of age.
Historically, respiratory delivery was accomplished using a small nebulizer based on reconstitution of the lyophilized Edmonston-Zagreb strain of the measles vaccine otherwise used for injection. This strategy has worked well and is generally referred to as the Classic Mexican Device or CMD. However, since these nebulizers use compressed air, a power supply is necessary and thus the delivery system does not lend itself to use in the more remote regions of the world. Additionally, there is tremendous vaccine waste due to the dead volume in the nebulizers, the inefficient utilization of the mist generated and to the very low room temperature stability of the reconstituted vaccine.
Recent developments in aerosol delivery include “rupturable membranes” technology. In these types of devices, a syringe without an injection needle is used as the means to pressurize the device and burst the films that define the ends of a capsule containing the vaccine, thereby expelling the dose for delivery. They are single use, disposable and contain no sharps. Published patent applications and issued patents related to these types of devices include the following:
Published US Patent Applications US 2005/0000514, US 2004/0163645, US 2004/0079363, US 2004/0011356, US 2003/0047184, US 2002/0092524, US 2002/0092523, US 2002/0092521, and US 2002/0092520. Additionally, U.S. Pat. Nos. 6,929,005; 6,782,887; 6,722,364; 6,644,309; and 6,443,152 describe this technology. These patents are incorporated by reference herein in their entirety.
The above-described technology is predicated on the ability of the patient to coordinate his or her breathing with the actuation of the device. However, young children, typically those under four years of age, are generally incapable of this timing. Furthermore, it may not be possible to communicate the need for timing to the patent.
Thus alleviation of the timing issue has been solved by providing a fixed volume chamber between the medicament delivery device and the patient, however, a problem of the conventional fixed volume chamber devices are far too expensive to be considered disposable, and/or they are not at all collapsible or are insufficiently collapsible to be carried conveniently in a briefcase, vest pocket, or the like. U.S. Pat. Nos. 4,637,528 and 4,641,644 disclose aerosol inhalation devices that are partly collapsible, but not to a generally thin, flat configuration. U.S. Pat. No. 4,953,545 discloses a chamber that is disposable but not collapsible. U.S. Pat. Nos. 6,202,643 and 6,550,473 describe a collapsible device; however, its integrated valve makes it an expensive device to manufacture. Furthermore, each of the device designs described in the patents above must be tailored to the target patient population. Therefore, a multitude of devices is needed to cover an entire patient population.
The retail cost of conventional chamber devices described above typically is as much as nearly $20.00 and some are as high as $60.00. This cost may be acceptable to patients having chronic conditions which buy a device that is tailor made to their usage, however, many patients need inhaler medications for only a short period of time, or only a single use as in the case of mass vaccinations, in which case the high cost of conventional chambers is very unsatisfactory, especially if a substantially lower cost alternative were available. Additionally, a costly inventory of multiple device designs would be needed with these devices such that various configurations are available for each patient type.
What is needed is a device and or method to aid in coordination of delivery and inhalation to patients of all ages. Additionally, it would be of benefit to have a single device which accomplishes this objective for the entire population of users.